The El Refugio mine, located in Choix, in the Mexican state of Sinaloa, is a notable source of beautiful specimens of the zinc carbonate mineral smithsonite. These specimens are often very colorful and display well under normal light. Some of this material also shows a deep, intense fluorescent response under short wave UV, usually in colors of blue and/or pink. This example consists of botryoidal pink/lavender smithsonite that shows a moderate, but intense blue fluorescent response under short wave UV. The size of this specimen is 70 x 56 x 17 mm, and it weighs 71 grams.
In the photograph above, a moderate, but intense, blue fluorescent response is seen under short wave UV (254 nm). This piece does not respond under long wave UV.
Same specimen shown under visible light.